MARINE CORPS BASE CAMP PENDLETON, Calif. – A squad of Marines patrolled into a city where they were greeted with unhappy shouts from a crowd of Somalis. Men and women dressed in warm clothing yelled at the Marines in their native language as they pointed at the weapons the Marines were holding.

As the Marines attempted to calm the locals using hand gestures, a simulated rocket-propelled grenade was fired from the rooftop of a school.

In an instant, the Marines of Bravo Company, 1st Battalion, 4th Marine Regiment, were under attack by role-players from the rooftops of neighboring buildings during a session at the Infantry Immersion Trainer.

The IIT is used to prepare Marines for several environments where they will deploy.

Ken Sokolowski, an infantry immersion tactics consultant, said the trainer is used to pull the Marines into the deployment environment. It uses sights, smells and local culture to create a realistic environment to help train Marines for their deployment.

The trainer has provided role players from the countries Afghanistan, Iraq and Somalia. The role players speak only in their native tongue and act as if they don’t understand English. The Marines must attempt to communicate using hand and arm signals or interpreters to speak for them.

“It’s hard to communicate with someone when you have no idea what they are telling you, and they can’t understand anything you say,” said Pfc. Charles Lynch, a rifleman serving with Bravo Co. “The locals could be warning you of a possible attack, or they could be stalling you for an ambush.”

The training is great for Marines because it uses problems Marines actually face during deployments like not understanding the native language and being unable to read signs, said Cpl. Eduardo Mendoza, an infantry squad leader serving with Bravo Co., who has deployed to Afghanistan and Iraq.

“This training is as close to real as it gets,” said Mendoza, a 26-year-old native of Manteca, Calif. “If we don’t stay alert, we could find ourselves under attack.”

The IIT is a great way to train small unit leaders by taking them out of their comfort zone, said Sokolowski, a native of Hayward, Calif. It forces them to make decisions under pressure.

“It’s hard to think when someone is yelling at you in a language you don’t understand,” said Lynch, a 27-year-old native of Coupon, Pa. “You have to start implementing your training to keep the guys to your left and right safe.”

Mendoza said squad leaders develop immediate action drills with their Marines to be better prepared for ambushes.

When the Marines were ambushed by the role players from atop the school, Mendoza yelled commands to his squad, telling them to find cover. He split the squad into thirds, sending one fire team across the street to flank the enemy.

His other fire teams suppressed the enemy as their fellow warriors closed in on the hostiles. Within minutes, the Marines breached the building and captured the attackers.

“The Marines performed well during their time here,” Sokolowski said. “I think they will be fully capable to perform when they deploy next year with the [13th] Marine Expeditionary Unit.”